Seriously, Donna can sing. She has a very nice voice with great tone and even has some power at times. She can sing on key too as anyone who has listened to any substantial amount of GD material from that era can attest if they chose to be objective about it. I'm not saying that she always did, but she did often enough to convince me that she can sing on key.
That said, she did have some bad habits in the earlier part of her time with the GD, but now that I have been listening to more mid to late 70s stuff, it appears she was at least working on them. That's not to say that I haven't heard songs where I think her live performance took away from the experience rather than adding to it, as I definitely have. I can also see how it would be easy for folks who are into the GD to just dislike her whole vocal style and I agree that she didn't really fit well with the band. Given that, I don't see anything wrong with people being happy that she left the band, and based on the above posts, she agreed she didn't fit and was probably happy to leave the band as well. For what it is worth, I think the band was at their best in the Brent years for a variety of reasons, one of them being that Donna didn't fit and they were better without her.
The "Sluggo" post, is either mean spirited or a joke, I don't think it matters much which. If it is the former, I think it is a little uncalled for, but IMO, if you charge money for people to see you perform, you open yourself up to all kinds of criticism as part of the deal. If you can't take criticism of your performance, whether it is constructive, mean-spirited, destructive, or ridiculing, best to limit your audience to your Mother.
It is also my opinion that Keith was a solid keyboard player and I generally enjoy his contributions. I think Brent was better with the instrument and I always enjoyed Vince's vocal performances both with the Dead and with the Tubes, but I find specific criticisms of Keith difficult to come by.
Mama Mama many worlds I've come since I first left home.